Remote control of desktop

[Lance DeVooght]

Hi all.

I haven't posted here in a long time, but I have a challenge that I hope to  
get help with.

I will be giving my mother a laptop (hopefully) with Kubuntu 10.04 
installed,

I want to be able to remotely login to her laptop and control her desktop.
That way I can fix any problems she runs into, such as the need to install 
a new application. I could also use it to walk her through any operation 
that she is unfamiliar with.

The problem is, mom has no broadband in her home. She lives in a very remote 
location in northern Michigan.

But, I was hoping that when she visits a McDonnalds or a friend's house 
where she can get on their wifi (yes she does get into the big city 
occasionally), then I could connect to her laptop.

However, in the above scenario she would not have an Internet routable IP 
address (using NAT) and also no ability (physically, or technically) to set 
up port forwarding on the router.

Is there a way to connect to mom under these circumstances?

TIA,

Lance